Ernst & Young on Thursday released results from a survey of 1,000 licensed U.S. drivers that found 10 percent of drivers would consider purchasing a plug-in hybrid or electric vehicle. That represents about 20 million American drivers, enough demand to sell out 2010 and 2011 electric vehicles.

Automakers are betting the electrification of power trains is the future of the auto business, as was clear from this week's North American International Auto Show in Detroit. But even as automakers prepare to produce tens of thousands of these cars, big questions remain over how strong the demand will be.

Some argue that there will be rapid uptake in certain regions, much the way the well known Toyota Prius hybrid has been adopted. The Boston Consulting Group forecasts that 25 percent of new auto sales in 2020 will be hybrids or electrics, with the bulk being conventional hybrids.

Yet there are still clear barriers to consumer adoption, including range, cost, and availability of charging stations at home or public places.

Ernst & Young found that 34 percent of respondents were willing to subsidize local charging stations. At the same time, their top reason for considering buying an electric or plug-in hybrid is to save money on fuel.